-LRB- CNN -RRB- -- A British report issued Thursday called for `` decisive action '' to contain the growing problem of piracy off the coast of Somalia .

`` We conclude that for too long there has been a noticeable gap between the government 's rhetoric and its action , '' said the 210-page report , issued by the House of Commons Foreign Affairs Committee . `` Despite nine U.N. Security Council resolutions and three multinational naval operations , the counter-piracy policy has had limited impact . The number of attacks , the costs to the industry and the price of the ransoms have all increased significantly since 2007 . ''

Over the past four years , the average ransom has risen from $ 600,000 to $ 4.7 million per vessel , with 2011 's total outlay reaching $ 135 million , the report said .

Those payments `` should be a matter of deep concern to the British government and to the entire international maritime community , '' said the report , which described the government as `` disappointingly slow to track financial flows from piracy . ''

Though some ships have begun taking `` more robust '' measures to defend themselves , pirates still face few repercussions for their actions , it said . In those cases where pirates are detained , some 90 % are released without charge , it said , noting that there is no reason why Britain could not assert jurisdiction over suspected pirates .

Simply returning suspected pirates to their boats or to land `` provides little long-term deterrence and has demonstrably failed to prevent annual increases in both the number of pirates going to sea and in the number of attacks . ''

The report cited Saferworld , a nongovernmental organization that works with grass-roots organizations in Somalia , in estimating that 1,500 to 3,000 pirates operate off Somalia 's coast . They typically range in age from 15 to 30 and are almost all male , uneducated and unskilled -- many of them from rural areas , it said .

They often carry small arms and travel in one or two skiffs , the report said , citing Capt. David Reindorp , head of the Defense Crisis Management Center at the Ministry of Defense , as its source . `` They will maneuver one of the skiffs to come alongside the vessel and they will throw up a line on a hook , a grappling rope or some form of apparatus by which they can climb up on to the freeboard of the ship . If they are detected during that , they will usually fire at the ship , generally in and around the bridge , aiming either to get the master to slow down or to clear their way on to the freeboard . Once they have got on to the ship , they will proceed to the bridge and take it over . ''

Negotiations are typically carried out by satellite phone and usually take three months to a year , it said .

Pirates have begun working from larger vessels , mother ships , which are stocked with food and fuel and have extended the areas vulnerable to attack , it said .

Though most hostages are released unharmed , 15 died last year , it said . Over the past four years , 3,500 seafarers have been taken hostage and 62 have been killed , it said .

The report applauded the government 's practice of using a number of different departments to tackle the problem , but said it `` lacks clear leadership '' and urged the government to `` provide a statement clarifying which department has the overall lead on countering piracy . ''

There is no lack of targets . Some 90 % of the world 's traded materials are shipped by sea , and 40 % of that -- 28,000 ships per year -- goes through the Indian Ocean , Gulf of Aden and Arabian Sea , the report said .

The report put the annual cost of piracy -- including insurance , prosecutions , security and ransoms -- at $ 7 billion to $ 12 billion .

In a statement , Foreign Secretary William Hague said the report will be discussed next month at a meeting in London . `` We will use the London Conference on Somalia to chart a way forward on the future political direction of Somalia , the vital humanitarian effort and the international community 's approach to tackling piracy . ''

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There is `` gap between the government 's rhetoric and its action , '' the report says

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The average ransom has risen from $ 600,000 to $ 4.7 million per vessel in four years

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Report is issued by the House of Commons Foreign Affairs Committee